Add safety checks and reenable Canvas2D/WebGL trace_tests.

Add safety checks and reenable Canvas2D/WebGL trace_tests.

The trace tests were disabled because they were flakily failing, whereas their
pixel_test counterparts were having no problems. This CL makes several small
changes.
  1. Additional safety checking in trace_test and pixel_canvas2d_webgl.
  2. Rename gl->temp_gl and canvas->temp_canvas to avoid potential namespace
  collisions with global object in pixel_canvas2d_webgl.
  3. Reenable trace tests.
  4. For consistency, try to grab the "experimental-webgl" context, then the
  "webgl" context.

BUG=595754
Committed: https://crrev.com/0f496000d1f33c9255621efbf6b88a8185a791cd
Cr-Commit-Position: refs/heads/master@{#383572}

[erikchen, 2016-03-25 18:38:39]

Description was changed from

==========
Add safety checks and reenable Canvas2D/WebGL trace_tests.

The trace tests were disabled because they were flakily failing, whereas their
pixel_test counterparts were having no problems. This CL makes several small
changes.
  1. Additional safety checking in trace_test and pixel_canvas2d_webgl.
  2. Rename gl->temp_gl and canvas->temp_canvas to avoid potential namespace
  collisions with global object in pixel_canvas2d_webgl.
  3. Reenable trace tests.

BUG=595754
==========

to

==========
Add safety checks and reenable Canvas2D/WebGL trace_tests.

The trace tests were disabled because they were flakily failing, whereas their
pixel_test counterparts were having no problems. This CL makes several small
changes.
  1. Additional safety checking in trace_test and pixel_canvas2d_webgl.
  2. Rename gl->temp_gl and canvas->temp_canvas to avoid potential namespace
  collisions with global object in pixel_canvas2d_webgl.
  3. Reenable trace tests.
  4. For consistency, try to grab the "experimental-webgl" context, then the
  "webgl" context.

BUG=595754
==========

[erikchen, 2016-03-25 18:38:55]

The CQ bit was checked by erikchen@chromium.org to run a CQ dry run

[erikchen, 2016-03-25 18:39:07]

erikchen@chromium.org changed reviewers:
+ kbr@chromium.org

[erikchen, 2016-03-25 18:39:08]

kbr: Please review.

[commit-bot: I haz the power, 2016-03-25 18:39:19]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1826343003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1826343003/1

[commit-bot: I haz the power, 2016-03-25 20:04:23]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-03-25 20:04:24]

Dry run: This issue passed the CQ dry run.

[Ken Russell (switch to Gerrit), 2016-03-28 20:09:08]

lgtm

[Ken Russell (switch to Gerrit), 2016-03-28 20:10:47]

Note: please also include bajones@ and zmo@ on reviews of GPU test changes.
Also, the changes to these tests in this CL should not have an effect, so let's
please keep a close eye on them after re-enabling, and disable them again if
they are still flaky.

[erikchen, 2016-03-28 20:18:07]

The CQ bit was checked by erikchen@chromium.org

[commit-bot: I haz the power, 2016-03-28 20:18:34]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1826343003/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1826343003/1

[commit-bot: I haz the power, 2016-03-28 21:36:33]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-03-28 21:38:00]

Description was changed from

==========
Add safety checks and reenable Canvas2D/WebGL trace_tests.

The trace tests were disabled because they were flakily failing, whereas their
pixel_test counterparts were having no problems. This CL makes several small
changes.
  1. Additional safety checking in trace_test and pixel_canvas2d_webgl.
  2. Rename gl->temp_gl and canvas->temp_canvas to avoid potential namespace
  collisions with global object in pixel_canvas2d_webgl.
  3. Reenable trace tests.
  4. For consistency, try to grab the "experimental-webgl" context, then the
  "webgl" context.

BUG=595754
==========

to

==========
Add safety checks and reenable Canvas2D/WebGL trace_tests.

The trace tests were disabled because they were flakily failing, whereas their
pixel_test counterparts were having no problems. This CL makes several small
changes.
  1. Additional safety checking in trace_test and pixel_canvas2d_webgl.
  2. Rename gl->temp_gl and canvas->temp_canvas to avoid potential namespace
  collisions with global object in pixel_canvas2d_webgl.
  3. Reenable trace tests.
  4. For consistency, try to grab the "experimental-webgl" context, then the
  "webgl" context.

BUG=595754

Committed: https://crrev.com/0f496000d1f33c9255621efbf6b88a8185a791cd
Cr-Commit-Position: refs/heads/master@{#383572}
==========

[commit-bot: I haz the power, 2016-03-28 21:38:01]

Patchset 1 (id:??) landed as
https://crrev.com/0f496000d1f33c9255621efbf6b88a8185a791cd
Cr-Commit-Position: refs/heads/master@{#383572}